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Topic: Another "Peacemaker" Question (Read 1345 times)

I'm at that stage where I decide where to slot my center sheeting for the control rod on my Aldrich "Peacemaker." I'm using a CF rod with threaded ends and ball links instead of GMA's "Z"-bent wire, which makes the elevator-horn length a bit more critical to the chord-wise slot dimension and structure of this kit model.

Since I've never flown a combat or "Flite Streak" type model, the 2" bellcrank, 5/8" rod arm, and 1/2" elevator-horn arm length on the plans seem like a pretty sensitive (touchy?) combination to me. Are they?

I'm using a 3" bellcrank with about the same bellcrank rod-arm length (within 1/32"), which would cut the near-neutral control deflection by about a third, for the same handle movement and elevator horn length. I'm looking for pattern-capable maneuverability without extreme sensitivity, but don't want to take the fun out of the model. I'd appreciate any input on whether the 1/2" elevator arm would give this kind of response on the "Peacemaker." I'd especially appreciate comments from those who have built "Peacemakers" on what they have used and liked. Thanks, guys!

P.S. The photos show that wing structure of this kit is not as on the plans. I added the 1/4"-square spars to duplicate appearance and aerodynamics of the original. There are structural shear webs for both leading- and trailing-edge sheeting. I'll probably need to cut into it some for rod clearance.

The bigger the bellcrank and the more angle it moves through, the better for leverage over control surface hinge moment, although hinge moment from a Flite Streak elevator and no flaps is pretty small. Pick a ratio of bellcrank pushrod arm length and control horn length that gets you the max elevator you want when the bellcrank is at max deflection. With that ratio constant, bellcrank pushrod arm length and control horn length are determined by control system structure. With the carbon pushrod and ball links, that shouldn't be at all critical. Then pick handle spacing to give you the feel you want.

The 1/4" spars, besides having authentic appearance and airfoil, will also give authenticity in flight by not having the wing fold.

Saw some fancy fiddling Saturday. James Ehnes played a new violin concerto which pretty much wore out his instrument.

Howard, that's a good plan, and I got up early today to explore with a little trig. I computed that GMA's geometry results in a lock-to-lock bellcrank motion that could drive the elevator vertical, if physically possible. So my 3" bellcrank should work OK with it's limits. A reasonable maximum elevator deflection should not take too much material off the t.e. box (although the stress riser is right there at the root). I computed that a .47" elevator arm would give me 45 degrees, and the 9/16"-arm (1/2" high) hole in one of my nylon horns would give a maximum deflection of 36 degrees. So, the remaining question is what the maximum deflection should be with such a tiny elevator. I don't have a feel for how effective small, short-coupled tails with such small elevators are on flapless planes. Any suggestions?

Greq, I may use a nylon horn or make my own, but I'll have to cut away more structure than I'd like for any but the nearest stock holes in the nylon horns I have on hand. I was wondering though, what size bell cranks you have used on your "Peacemakers" and especially whether you have used the 3/8" hole spacing (for 7/16" arm length) for the elevator horn with the 2" bellcrank, as shown on the plans. I haven't ever flown 'Streaks or Peacemakers, but yours sound as though they handle as I'd like mine. Thanks for sharing your experience.

on 20 / 22 Oz solid foam wing peacemakers covered in cardboard with silver swallows that want loop unless you whip them for 5 laps climbing ,Dive and whip hard . Then theyve got a 50 % chance of not bellying in coming out off it !

P.S. you can scale up the Aeromodelor PLAN 150 % and the mainplane will be 48 in , before the Tips .

60 ft of .012 on a Std One on a calm summers evening , with the OS 20 , is a rewarding experiance .

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Any suggestions?

Oh Dear . ! .

45 Deg , unless its 60 Deg . Which allows you to run back , get the lines tight , and stall turn ( rotate ) it ( hopefully ) before it goes in .If someone cocked up something somewhere .

The One Above , Id Initially used a 1/4 + Chord Elevator , But after the first flight , at about 90 mph , on 60's ( The 1958 Fox 59 manual says " 11 x 7 " is the correct prop . )Cut it to Std. Chord ( + 50% to match the rest .)

UNFORTUNATELY one day , in a gale , on a wingover , I Thought ' somethings a bit odd ' and gave full UP , at the top of the circle ,60 Deg. Circuferance Later , Id Chickened out and slamed on Full down , simultaeneously with ' It ( finally ) started to bite .' Now being on Full Down , and 60 Deg Later being 30 Deg. below ground level ,There was a problem .

Ea wing Rib was in 3 pieces , either horizontally or vertically .The Gods Relenting for a moment & a plastic bag being close to hand ,all the ' peaces ' were quickly salvaged . All 80 + off them .Glued together , with a full new packet of pins consumed ,there were enough slivers to replace the wood in front of the tipweight if I glued them together .But I lashed out and used a NEW piece or 1/2 x 1/8 balsa there .

Set the Handle Up , so that 45 Deg odd is your normal comfortable ' wrist movement ' ,then when theres a slight irregularity , you can run like stink , jump back , and hold the Handle Flat ,( Horizontal ) So That ITS ON Full Deflection ,The Jolt as the lines come tight often pulls out the Inertia and gets the Stall turn required to avoid the abrubt termination of progress ,And the Wings Falling Off .Unless youve put the flaps thru the Fuse , butt jointed .

It might pay to put the C G fwd a notch with the bigger elevator .

The Memories of over a Dozen Peacemaker are of the occasional ' Sliding on ice ' *; feel ,after its apparently stalled , after a bump in the air , hitting the slipstream , or a seagullhad disturbed the atmosphere adjacent .Actually Peacemakers are good for dogfighting seagulls .

* This Residual Recurrent imprint on the consiousness must have been why I initially used the wider chord on the blue & white one , 30 years later .And regretted removing it .

Thanks for the story and suggestions, Matt. I have decided already to carry the flaps through the fuselage, since I don't trust myself to get them on right otherwise (never having built a Flite Streak or Peacemaker. I'm getting the idea that my choice of vintage engine won't quite cut it. The club guys say that if I use a .15, it should be modern. Oh, well. I have a little time to see to that. I got the main wing structure done today.

I was always taught to respect my elders, but it keeps getting harder to find one.Today I broke my personal record for most consecutive days lived.John E. "DOC" Holliday10421 West 56th TerraceShawnee, KANSAS 66203AMA 23530